Cell-tester.



J. O. LUTHY.

I CELL TESTER.

APPUCATION men FEB. 26. 1913.

1,202,078. Patented Oct. 24,1916.

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" JOSEPH o. mm-Y, OF SAN ANTONIO, TEXAS.

CELL-TESTER.

macabre.

, Specifiation of Letters Patent.

'PatentecIOet; 24, 1916.

"Application filed' February 26,1913. Serial No. 750,859.

T aZZ whomit mag c'oncem Be it known: that I, JOSEPH -O. 'LUTHY, a

citizen of the Republic" of Switzerland, re-

siding at San Antonio, "in the county of -BeXar,'-Stat'e o'fTeX'a s,have invented cer- -tain-new and useful Improvements in *Qell- Testers;and Pdoherebyd'eclarethe following to "be a full, clea'r, and exactdescription of the invention, such-as will-enable others skilledin the"art'to which'itappertains'to make and use-tliesame.

The invention relates-to-a simpleand'efficient portable' d'evice fortesting "battery- -c'ells""and the like in, order. to indicate whetherthe *cellsu are delivering the normal amount of currentg'or'in otherwords,

q'wheth'erthe voltage ot *the "cells has or "has, not dropped below apredetermined minimum.

In its preferred form, the invention "comprises a small closed casingcontaining an eleetro magnet having a movable armature associated "witha manually set indicating element,-themagnet'being wound to respondto'eurrent of a givenniinimum voltage to attract the armature andthereby cause the indicating elementto operate through an opening in thecasing, thefelement preferably being so constructed and arranged thatllDOllthGitClillfltiOIl ofthe armature and the visual indicatingelement, the circuit 1 form of 'a -right-angle, the base of which is"mounted by suitable screws or the like upon a st'rip; of insulation lattached: to one 'side *wall'of. the casing; Pivoted-atb inthe upthroughthe r apparatus will be broken,

thereby preventing unnecessary waste of the battery "current, afterwhich "the parts may be reset-by hand for asubsequent test.

111 the accompanying drawings, Figure 1 is a rearsec'ti'onal elevationof a preferred type of apparatus involving the invention; Fig. Qisafront sectional elevation of aem'odified form of "the invention; Figt3is a corresponding viewof a further modificationq-F-ig; 4 is'a'sectional side "elevation of the form shown in Fig. 3.

Referring to Fig. 1 'of' the drawings, the

numeral 1 indicates a box-like "casing of brass oi-other suitable metalwhich is pref- Mounted in the lower part "of the casing isan'electro-magn'et 2 with the'poles of which cooperates a springarmature 3 bent in the per'partotthe casing is a swingin'garm or lever 5'whlch is connected by a retractile spring 7 attached to a terminalstud'8 in the side wall ofthe casing, said springbeing attached to thelever 5 by'meansof an adjustable set screw '12, wherebythe tension ofthe spring may be regulated. Intermediate the endsof the lever-5thereismounted a pin or stud 8 which p'rojectsthrough an arc-shaped slot 10in'the front face of the casing, and on the outer-end of-Jsaid studthere is'secu-red a-sm'all'knob '9." The lower end of thelever 5 isadapted to be engaged by an inclined nose'piece onthe'end ofthe armature3, as indicated, so thatwhen the armature is inietract'ed position, thelever '5 will'b'e held at oneside of the vertical axis 'ofthe casing,against the'tension of spring 7,-but'when the armature '3'isattracted bythe magnet 2, thenose'of said armature will pass out *ofengagement withthe end of the lever 5 and permit said lever to be pulled over by thespring 7 to an inclined position on the opposite side of the verticalaxis of the casing, thereby moving the pin 8 in'the slot 1O from one endto the other thereof and until the lever engages a stationary stop '11mounted on theinside of "the front wall of the'casing. The movement ofthelever 5 under the action of'thespring 7 causes the saidlever todeliver a sharp blow against the stop -11, thereby producing an'audiblesignal in additionto the visual indication effected bythe movemento rthe knob 9 across the slot.

In the form shown, the magnet Qisdiffer'entially wound to respond 'tothree different vo"ltages,'as for "example, one and onel1Llf,"SlXand'ten-volt's. "For'testing for the lower voltage, as for example, thatdeveloped by-a single dry cell, the left-hand coil of the magnet 2 isconnected by wire 20 to'an insulated'stud 17 mounted in the bottom ofthe casing, said wire being connected at its other end to the crossconnecting wire 21 be tween the spools. For the highest voltage, thecomplete windings 'of both spoolsare connected in series with a centralinsulated terminal stud 1.6 by means of a wire '19, and for theintermediate voltage, a portion only of the winding of the right-handmagnet is connected to aniinsulate'd stud 15-in'the bottom of the casingby a, wire -18,the fractional windingetthe right hand spool being comnected in series with the whole winding of the left-hand spool. Saidleft-hand spool is in turn connected by wire 22 with the armature 3.

In operating the device as described, to test a single cell, forexample, to ascertain whether itsvoltage is sufficiently high to retainthe cell in operation, contact is made between terminal stud 17 and oneterminal of the cell, and between the casing 1 and the other terminal ofthe cell, either by means of short sections of wire or by bringing thestud 17 and the casing 1 into direct contact with the battery terminals.If-the voltage of the cell is normal or higher than normal, theleft-hand coil of magnet 2 will be energized and attract the armature 3,thereby releasing the lever 5 and permitting the same to be pulled overagainst its stop 11, by a spring 7, and moving the stud .8 to theopposite end of the slot'lO, giving both a visual and audible indication that the voltage of the cell is nor- 3 mal. If the voltage ofthe cell is below normal, the current flowing through the coil of magnet2 is insuflicient to attract the armature and noindication is given, butthe armature remains in retracted vposition,lockingthe lever 5 againstmovement. The complete circuitefl'ecting the operation aforesaid is-asfollows: From one terminal of the cell. to be tested through insulatedcontact stud 17 wires 20 and 21, the left-hand coil of magnet 2, wire22, armature 3, lever 5 to the metallic casing 1 back to the otherterminal of the cell which isin electrical contact with said casing.Immediately after the armature is retracted, the lever 5 moves out ofengagement with the armature 3, thereby breaking the circuit, so thatpractically none of theenergy in the cell is wasted in the test. Theapparatus may be immediately reset for. a. further test by moving thelever in the opposite direction, against the tension of spring 7 bymeans of the knob 9 on the end of the stud 8 projecting through the slot10 and untillthe lower end of the lever snaps behind the nose on the endof the armature 3. To test a battery or series of cells for theintermediate voltage of six, the right hand stud'15 is connected withone terminal of the battery and the other terminal of the battery iselectrically connected with the casing 1. The operation will be asbefore described, except that the current will flow from the batterythrough terminal 15, conductor 18 through a portion of the right-handcoil of magnet 2, thence by conductor 21 through the entire left-handcoil of said magnet,

thence by conductor 22 to armature 3, lever 5, through the metalliccasing 1 backto the battery. If the voltage of the battery tested isequal to or greater thanthe normal of six required, the magnet isenergized sufliciently to attract its armature and the operation is ashereinbefore described, namely, the lever 5 is released and pulled overby its spring 7 and the circuit to the battery is broken between thearmature 3 and the end of the lever 5.- A similar operation takes placewhen the test of the maximum voltage of ten is desired, in which case,the interme-' diate stud 16 is connected through one terminal of thebattery and the current flows by way of wire 19 through both coils ofthe magnet 2, wire 22, armature 3, lever 5, to the casing and thenceback to the battery.

In the modified form of the device shown in Fig. 2, there is provided acasing 1 similar to that shown in Fig. 1 having therein asolenoidprovided with a winding calibrated to attract the central coreof the solenoid when a current having the desired minimum voltage passesthrough the coil of the solenoid. The coreof said solenoid consists of amagnetic section 3 to which is attached a non-magnetic metallic section3*, of brass or the like, the upper end of which projects through anopening 10 in the top of the casing. A spiral spring 7 surrounding theupper end of the section 3 tends to force the armature downward so thatthe upper end projects only a slight distance through the opening in thecasing 1 The lower end of the armature 3 is provided with a contact head3 above which is a groove or notch 3. 7 The contact head 3 is adapted tonormally engage the forked end of insulated contact stud 6 mounted inthe bottom of the casing. 'A leaf spring 5* attached to the lower endof'the solenoid is provided with a curved nose 5 to snap into the groove3 on the lower end of the core, when the core is attracted and hold thecore in its attracted position. One end of the coil of the solenoid isattached by wire 18 to an insulated contact stud 8 mounted at anyconvenient point on the casing 1 The other terminal of the coil of thesolenoid is connected by a wire 22 directly to the metallic casing 1*.shown, the device is designed to give an indication of a current of onespecified minimum voltage only, but obviously by connecting the coil insections to several terminal studs corresponding to 8*, as 1n Flg. 1,the

instrument -may be calibrated to indicate other voltages, as will beunderstood. In operating this form of the apparatus, the armature coreof the solenoid is pressed down by the finger until the lower end 3' 6and electrical connection is established between said stud and oneterminal of the battery, and between stud 8 and the other terminal ofthe battery or cell. The current will then flow from the battery throughstud 6 solenoid core sections'3 and 3 to the casing, wire 22, throughthe coil of solenoid 2, thence by wire 18 to insulated stud 8 back tothe battery. If the voltage thereof engages the end of the contact studofthe cell or batterytested is equal to {that -7?-.and:1draw the core:up into the solenoid,

thereby vprojecting :the end of the section 3 -of the core throughathejhole in the :upper part ofv :the casing and causing the nose 5ofspring-5 to snapinto the notch 3 on the endof the core and hold thecore in its at- I tracted positionunti-l it is forced down by the fingerof the operator tozits normallower position. Vhen the core 8 isattracted or drawn up into the solenoid, the end 3 thereof passes out-ofcontact with the stud 6 and breaks the circuit. If the cell tested doesnot develop the desired voltage ,ythe

current flowing throughthe .coil of armature '2 is :not. sufficient toattract :the core and the device gives no indication.

In the modification 0f the apparatus shown in Figs. '3 ands, there isemployeda metallic casing I generally like those here tofore explained,inwhich isHmoun-ted an ordinary two-pole :magnet f2gwith :the poles ofwhich cooperatesahail-shaped armature 3 which is pivoted at 4L t0 thesides of the magnet. Between the coils of the magnet is located anindicator rod 5, the upper end of which extends through a circularopening 10 in the top of the casing. Said rod is guided in suitablebracket pieces 7 supported by the magnet frame and is actuated by ahelical spring 7 which tends to force the end thereof out throughtheopening 10 when said rod is released. The rod 5 is held in its retractedposition, against the tension of its spring 7, by means of a latchmember 3 rigidly attached to the middle of the swinging armature 3 andcooperating with a notch. in the lower end of the rod 7, as shown inFig. 4. A leaf-spring 3 attached to the casing 1' bears at one end onthe armature 3 and forces the lower end of the same toward the rod 5, sothat the latch 3" thereof will be in position to engage the notch in therod 5' and hold said rod in its retracted position. One end of thewindings of the magnet 2 is attached by a wire 18 to insulated stud 6carried by the casing and the other end of said winding is attached by awire 22 directed to the casing. To operate this form of the apparatus,contact is made between the one terminal of the cell or battery to betested and insulated stud 6, and between the other terminal of the cellor battery and the casing 1. The current then flows from the cell tostud 6, wire 18, coils of magnet 2, wire 22 to the casing, thence backto the cell, the opposite terminal of which is in electrical contactwith said casing. If the voltage of the cell or battery is lower. end.:of; Elllle; nod 5, thereby ereleasing -.-s'aida'od and permitting theupper end of the same to .be forcedzoutward through :the. op.en-'

ing. 10; :in; :the top of; :the casing until the :movement is arrestedbyy'the stop 5. The --projectionofthe end of the rod 5 andwthe sharpzblowidelivered by the stop 5 on the casing willgiveboth a visualandanaudible.

indication that :the instrument has operated --and that the voltage ofthe current tested --is atleast equal to that for which the instru-,ment iscalibrated. 'lfzthe voltage is, below normal, :the instrumentwill not be operated but the .rod 5 :will remain locked in-i:ts--retracted position. After: ithe instrument' has been operated, itis reset :by forcing :the rod downward against the :tension'of itsspring :until the lower end ofsaidrod is engaged- -by :the latchon:saidvarmaturezand the msstrument iskready forafurtheritest. :In't'his"Storm of the apparatus, no means for breaking the .circuitas soon as anindicationuhas been (obtained is provided, but obviously the same meansfor-effecting this :obj ect {may :be

employed, as indicated in the modification show-n in 'Fig. 2. t

WVhile the breaking of the circuit is a desirable object, it is notessential to the successful use of the apparatus and the instrument maybe constructed and successfully applied without this structural andoperative feature. The instruments are preferably constructedsufliciently small to be conveniently carried in the pocket or in atoolkit, and inasmuch as the internal mechanism is entirely protected bythe closed casing, it is not liable to injury or derangement, even whencarelessly used, but affords a simple, reliable and efficient devicethat may be employed by careless or unskilled persons without dangereither to the user or to the instrument.

What I claim is 1. A portable cell testing device, comprising a portablecasing having an opening therein, an electro-magnet having a movablearmature in said casing held against movement in all positions of thecasing until actuated by the magnet, and a manually set indicatingelement associated with said armature and movable through said openingin the casing when the magnet is energized, said indicating elementbeing operable, regardless of the position of the casing.

2. A portable cell testing device, comprising a portable casing havingan opening therein, an electro-magnet having a movable armature in saidcasing held against movement in all positions of the casing untilactuated by the magnet, a manually set indicating element in the casingmovable through said opening when the magnet is energized, and meansassociated with the armature to spring 3,uthereby withdrawing athe latchi .8 from engagement-with the notch? in; the

hold theindicating element in set relation, said indicating elementbeing operable, re-

' gardless of the position of the casing.

' movement in all positions of the casing until actuated by the magnetand the indicating element being operable, regardless of the position ofthe casing. r o 4. A portable cell testing device, comprisinga portablecasing having a slot therein,

an arm in said casinghaving a stud moving in said slot, means fornormally retracting said arm, and an electro-magnet in said casinghaving an armature normally restraining the movement of said arm andreleasing said arm only upon energization of themagnet by passage of acurrent of requisite strength,

Copies of this patent may be obtain'ed for the said arm being operableto move to its retracted position when released, regardless of theposition of the casing.

' 5. A portable cell'testing device, comprisring a portable casinghaving a slot therein,

a pivoted arm in said casing having a stud moving in said slot, meansfor normally retracting said arm, an electro-magnet in said casinghaving an armature normally restraining the movement of said arm andreleasing said arm only upon energization of the magnet by the passageof the current of requisite strength, and a circuit for said magnetincluding terminal connections and the armature and arm aforesaid, whichcircuit is broken by the disengagement of the armature and arm, the saidarm being operable to move to its retracted position When released,regardless of the position of the cas-' JOSEPH o. LUTHY. Witnesses:

ARTHUR L. BRYANT,

CHAS. J. ONEILn live cents each, by addressing'the Commissioner ofPatents.

Washington, I). 0.

